Which of this lenses will give me better MINIMAL WORKING DISTANCE for shy bugs, butterflies and dragonflies - Sigma 150 is sufficient for this task or 180 would be better?

Also I know that I would need faster shutter with Sigma 180, so it is some disadvantage from the beginning but IMAGE QUALITY seems for me almost the same as the almost the same weight.

Any advices? I'm also aware that Sigma 180 is more expensive but in the terms of focal length not too much either..

Well, the MFD of the 150mm at 1:1 is 38cm, the MFD of the 180mm at 1:1 is 46cm. So the longer lens wins even at 1:1. At lower magnifications the 180mm will have a 20% (=180/150-1) advantage at MFD which should translate into an almost equal advantage with the working distance (front-lens to subject):
The 180mm is 43mm longer than the 150mm which reduces the working distance accordingly (both lenses remain constant length even when focusing to MFD). So at 1:1 the working distance of the 180mm is only 4cm longer (24cm instead of 20cm) - which is not really a big benefit. At magnifications of 1:4 you gain around 20cm (90cm vs. 70 cm).
Judge for yourself whether this is enough to influence your decision. Imho this is not a decisive factor compared to e.g. the gain you would get from using a 300mm lens. I personally would go for the 150mm. I have it and I have seen nothing sharper yet!

http://www.juzaphoto.com/eng/photo_galleries.htm - which made me believe that both 150 and 180 are superb lenses (also gave me idea how the photos look with Sigma TCs 1.4x and 2.0) BUT now I realize that he was using this lense on FF which makes quite big difference due to the crop factor matter I guess. Still in IQ matter seem very close (both S150 and S180).

Do you think that normal guy (who doesn't lift weight) like me will have any problems with handling Sigma 150 (895 g) without a TRIPOD - as I consider using it WITHOUT tripod and also with natural light (at least at the beginning, as I don't like the idea of using tripod with the bugs either and also some ring-flash light seems to me to be unnatural one which I simply don't like..)).

And as an amateur I was comparing MAINLY the IQ between Sigma 150, Sigma 180 and Canon 100/2.8 Macro Usm which gave me a conclusion that both Sigmas are superb lenses just don't know if good for handholding (some folks have spoken that it is so uncomfortable with handholding..).

I'm also no friend of a tripod either. I sometimes try to use a monopod but did fail miserably due to lack of proper technique There are some thing to consider:
- a lens with image stabilization is of very high value as you magnify shake when going 1:5 or beyond - unfortunately at those magnifications the efficiency of IS/VR/OS/VC seems to deteriorate to 1-2 stops - a lens with max aperture of f/2.8 seems a good bet here, as you get shorter shutter speeds to compensate for (magnified) shake - unfortunately nobody ever uses f/2.8 on macro shots because the dof would be so razor-thin! - shooting bugs or other creepy-crawlies has the advantage that they often crawl around on the ground. Just get your trousers dirty, kneel in front of them and use your elbows as support. That way you're almost as stable as with a tripod

So yes: I miss IS/VR on my Sigma 150/2.8. But choosing between selling my Nikon 105/VR and my Sigma 150/2.8 is an impossible task for me, because both lenses have their merits

I've also read that A is trully closer to f/5.6 than f/2.8 at 1:1 magnification.. and as you've said having A like 2.8 at close distances wouldn't help too much due to the very shallow DOF..

It has I guess some meaning in some normal shooting situations like bird shooting.. But yet it is "only" 150* (240 with 1.6 crop factor), so the possibilities are highly limited though it is always better than Canon 100 (160) Macro Usm if we don't add the fact that macro lens has some other primary job to do (I also consider some portrait job here - but primary is still primary..).

* I don't speak about TC as I consider just the "pure" "power" of the lenses..

You know, before I took the plunge and got the Nikon 70-200 VRII I was constantly looking for some sharp f/2.8 "long" tele-lens. I tried the old Nikon 180/2.8D which did not satisfy me, had the Tamron 70-200 and gave it back. But the Sigma 150/2.8 would stay on my lens-portfolio if I would not already have the Nikon 105/2.8 VR macro lens.
Because the 70-200/2.8 seems on the same IQ level as the Sigma 150 and is stabilized and as a zoom much more versatile - and I don't need two macro lenses...
So tough task to decide which macro has to go now

I also have in mind that comparing Canon 100/2.8 Macro USM to Sigma 150, the MWD is "only" 5 cm gap but if I get it right with 1:2 magnification 5 "becomes" 10, at 1:3 10 "becomes" ca. 15 and so on, so the MWD is some factor here.. And I've heard that for dragonflies U need 1:3/1:4 magnification or so (correct me as maybe I remembered the figures wrong..) which is then a really HUGE difference.. 15 cm if it comes to flying subject is really something I guess!

So if at 1:3 the distance with Sigma would be ca. 60 cm then with Canon it would be "just"/only 40.. now it seems to be big difference..

And also many times on my Fuji S20 Pro I had problems than maximal magnification was available from the distance 10-15 cm or so (don't remember the exact figures..), as I've found "super-macro" option to be very unpractical one.. Still the magnification was I guess really poor even with dragonflies not "phenomenal" .. looked like much less than 1:1, maybe 1:5 or so..

Last edited by Introverder on Thu Dec 17, 2009 8:51 pm, edited 1 time in total.

Dragonflies and 1:3 - 1:4 go perfectly together as you see here:
But this was shot with a Sigma 300mm f/4.0 lens at 1.2m - 1.5m. I would have never got the shot with a Sigma 150mm or 180mm because 1m seems to be the flight-distance of those dragon-flies, unfortunately

And also many times on my Fuji S20 Pro I had problems than maximal magnification was available from the distance 10-15 cm or so (so-called "macro mode"; don't remember the exact figures..), as I've found "super-macro" option to be very unpractical one (due to the shadow matter and of course the M was again weaker.).. Still the magnification was I guess really poor even with dragonflies not "phenomenal" .. looked like much less than 1:1, maybe 1:4 or so.. No chance of catching them with this camera either.. not even mention some smaller bugs :/..

than maybe Sigma 180 would be better to the task giving ENOUGH "room" for flying objects to catch (have you tried hardly with S180 to make so).. BUT then maybe to far to make some "normal" macro - like "sitting" bugs or so and flowers..).

I have these "second" thoughts as Sigma TC (+ S150) would cost me more than "pure" Sigma 180 BUT again if tests are right then Sigma 150 is superior to Sigma 180.. And I always dreamed off catching these creatures you know by myself ; ).. Seen so few of these EFFECTIVE SHOTS on the net, makes me believe it is really something.

I must clearly state that I had never tested a Sigma 180/3.5! All figures in the posts above are calculated from the technical data published by Sigma.
I still believe them to be correct because many times the formulas were proved to be sufficiently exact, but I cannot guaranty for them...
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Yeah, 90cm vs. 70cm may make or brake a shot. But my main point was: Even 90cm may be too close for some of those critters

And if I get the magnification matter right, then if CMOS matrix from 50D is 22,5 x 14,8 mm, then at 1:1 magnification the same sized object would cover the full "frame"/image, right? Or in other words the 1cm long ant would be the same 1 cm on the matrix, yes?

- > So the 1:2 magnification would be like covering the rectangle of 45 (22,5 x 2) x 29,6 (14,8 x 2), right?

And at 1:3 magnification would be sth like covering the rectangle of 67,5 x 44,4. I drew such rectangles like the ones given to 1:1, 1:2 and 1:3 magnification and now I have some idea of how big would some insect would be on the frame.

I would be INTERESTED for these figures especially for the lenses "in bold":

I will add the complete data-set for the Sigma 150 and Nikkor 105/VR.
Let's just make sure that everyone understands the same:
- MFD = minimum focus distance = distance from subject to sensor- MWD = minimum working distance = distance from subject to front-filter-thread (not front-lens, as some lenses are deeply recessed)
And we'll be talking only about MWD, not MFD here, right?

I would do it by myself JUST didn't know where to look :/ and from specifications I am capable to measure 1:1 magnification and this would be from a sensor though too (MFD).

Ok, now I get it if I would subtract lens length from the MFD, then I would get "pure" MWD, at least for the 1:1 magnification..

Is there any formula/pattern to count the exact 1:2, 1:3 and so on magnifications?

And I've come across another matter.. I was trying to get some approximately data with the magnifications/distances but still trying to guess from pics is a really tough task (and very unprecise either..). To be honest I haven't found any SINGLE shot with the scale-table from Sigma 150 lens (I mean where I could look to these figures right) :/.. Just didn't know where to look for such data..

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MWD as I've found it to be much more important for practical using, shots.

For 1:1 magnification (at least for these lenses..) I've found data (still don't know where to look for 1:2, 1:3, 1:4, 1:5 and 1:10 magnifications info..):

For the Sigma 150mm lens, I'm reading the focus distances off the lens scale as follows. You will need to subtract both the lens length to mount, and the distance from lens mount to sensor for Canon body if you want the working distance.
1:1 38 cm
1:2 ~50 cm (estimated, not exact as markings not aligned)
1:3 ~64 cm (estimated, not exact as markings not aligned)
1:4 ~75 cm (estimated, not exact as markings not aligned)
1:5 ~90 cm+ (slighty more)
1:10 ~1.5m (estimated, not exact as markings not aligned)

For the Sigma 150mm lens, I'm reading the focus distances off the lens scale as follows. You will need to subtract both the lens length to mount, and the distance from lens mount to sensor for Canon body if you want the working distance.1:1 38 cm1:2 ~50 cm (estimated, not exact as markings not aligned)1:3 ~64 cm (estimated, not exact as markings not aligned)1:4 ~75 cm (estimated, not exact as markings not aligned)1:5 ~90 cm+ (slighty more)1:10 ~1.5m (estimated, not exact as markings not aligned)

Thanks popo,

so the MWD for Sigma 150 would be (substracting 18 cm is here needed I believe):